Spark plug



Aug. 14, 1923. 1,464,923 I G. T. DOCHTERMANN SPARK PLUG Filed Jan. 23. 1922 Jfiventon his e y.

Georye 1717 ochtermnn;

Patented Aug. 14, 1923.

UNITED STATES GEORGE T. DOCHTER-MANN. OF PASSAIC, NEW JERSEY.

SPARK PLUG.

Application filed January 23, 1922. Serial No. 531,123.

T all whomit may concern:

Be it known that I. Gnonon T. DOCHTER- MANN. a citizen of the United States. and a resident of Passaic. in the county of Passaic and State of New Jersey, have invented certain new and useful Improvements in Spark Plugs, of which the following is a specification.

This invention relates to spark plugs for internal combustion or explosive engines, and its object is to provide a device of the class specified in which the spark is materially intensified in its passage and its efficiency correspondingly augmented.

Another object is to provide a spark plug comprised of relatively few parts, simple and inexpensve to manufacture, easily assembled and installed. and not readily liable to derangement or failure.

These improvements comprise features which will be clearly described in this specification and illustrated in the accompanying drawing, in which Fig. 1 is a longitudinal sectional view of the preferred embodiment of a spark plug made in accordance with my invention.

Fig. 2 is a plan view of the conductor in detail.

Fig. 3 is a fragmentary sectional view, similar to Fig. 1 but showing a modification in structure.

The scale of all three view is the same.

Referring to the drawing, tubular body 10, of any approved design, is provided with screw threads 11 at its base for maintaining the plug inposition for use. The bore 12 of body is enlarged at its outer end, as at 13, to provide a seat 14 and is provided with interior threads 15 to engage hollow clamp nut 16.

Disposed on seat 14 is a ring 17 on which is seated the shoulder 18 of a tubular insulator member 19. the upper beveled surface of shoulder 18 being centered and held firmly in body 10 by the correspondingly beveled end of clamp nut 16, through which the body of said insulator extends.

The outer end of insulator 19 is formed with reduced extension 20 to which is fixed ring 21, screw threaded upon its exterior to receive terminal cap 22 from which extends a threaded stem 23 engaging lock nut 24 by which the terminal of the electric conductor, not shown, is secured.

A central passage 25 extends as usual longitndinaily through insulator 19. its inner end being enlarged to form recess 26. this passage and recess being'suited to receive the conductor, as shown in detail in Fig. 2.

Said conductor comprises an enlongated bar or rod element 27 having a transverse the opening in insulator 19, its upper end extending into space 32 below cap 22, out of contact therewith, so that when current is encircuited a jump spark is obtained of increased intensity.

The prongs or branche 29, together with the adjacent central portion of bar 27, are secured in recess 26 by means of cement 33, the bar extension 30 projecting outward beyond body 10. so that head 31 is slightly beyond converging web 34, formed with body 10 to act as a conductor, and spaced as usual to clear conductor member 30 and 31 in producing an effective operating spark.

In order to further intensify the spark, a gap 35 is formed in the conductor by removing that part of bar 27 immediately adjacent transverse member 28, as shown in Fig. 1. y

In the modification shown in Fig. 3, bar 27 is continued, as at 36, and threaded directly into lock out 24, the current passing uninterruptedly to the gap 35, and then jumping to member 30 of the conductor.

By the foregoing disclosure, a simple and effective type of spark plug is set forth, in which the delivered spark is intensified and which, due to its peculiar construction, is

capable of extended service.

I claim:

1. A spark lug including in combination a tubular insu ator having a seat in its lower end, a conductor comprising an elongated body having about midway its lengthoppositely branching members each having an arm lying substantially in parallelism with said body, said arms being adapted for mounting in the insulator seat.-

2. A spark plug conductor comprising an elongated body having about midway its length oppositely branching members each having an arm lying substantially in parallelism with said body.

3. A spark plug including in combination a tubular insulator having a seat in its lower end, a conductor comprising an elongated body having about midway its length oppositely branching members each having an arm lying substantially in parallelism with said body a portion of said conductor body and said arms being adapted for mounting in the insulator seat. and means tfor securing said parts in said seat.

4. That improvement in the art of making spark plugs where n 15 provided a tubular insulator having a seat in its lower end, a

- conductor havingjan elongated body within saidtubular insulator, said conductor pro- 

